Allocated but unannounced space
Every block here was allocated or assigned by a regional internet registry, and none of them appeared in any routing table we collected at our last snapshot — neither as a route of their own, nor covered by a larger announcement, nor carved up into more specifics.
“Unannounced” does not mean “unused”
Plenty of allocated space is deliberately kept off the public internet: private interconnects, lab and lawful-intercept ranges, networks reachable only inside one operator, and space held in reserve. Some of it is announced somewhere our collectors cannot see, which is a limit of our vantage points rather than a fact about the block.
It is also a snapshot, not a history: a block announced yesterday and withdrawn this morning appears here today. Nothing on this page means a block is unallocated, available, or free to announce.
Browse by registry
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Countries with unannounced space registered through ARIN, largest first.
Unannounced blocks registered through ARIN
30,461 blocks match, ordered by prefix.
| Prefix | Addresses | Registry | Country | Allocated |
|---|---|---|---|---|
| 192.75.198.0/24 | 256 | ARIN |  US | 28th Apr 1995 |
| 192.75.2.0/24 | 256 | ARIN |  CA | 8th Aug 1990 |
| 192.75.20.0/24 | 256 | ARIN | CA | 11th Oct 1990 |
| 192.75.208.0/24 | 256 | ARIN | CA | 18th Dec 1991 |
| 192.75.21.0/24 | 256 | ARIN | CA | 11th Oct 1990 |
| 192.75.210.0/24 | 256 | ARIN | CA | 20th Apr 1993 |
| 192.75.212.0/24 | 256 | ARIN | CA | 2nd Jun 1992 |
| 192.75.22.0/24 | 256 | ARIN | CA | 11th Oct 1990 |
| 192.75.230.0/24 | 256 | ARIN | CA | 18th Dec 1991 |
| 192.75.231.0/24 | 256 | ARIN | CA | 18th Dec 1991 |
| 192.75.232.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.75.233.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.75.234.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.75.235.0/24 | 256 | ARIN | CA | 30th Dec 1991 |
| 192.75.248.0/24 | 256 | ARIN | CA | 6th Jan 1992 |
| 192.75.249.0/24 | 256 | ARIN | CA | 6th Jan 1992 |
| 192.75.25.0/24 | 256 | ARIN | CA | 12th Nov 1990 |
| 192.75.250.0/24 | 256 | ARIN | CA | 6th Jan 1992 |
| 192.75.251.0/24 | 256 | ARIN | CA | 6th Jan 1992 |
| 192.75.252.0/24 | 256 | ARIN | CA | 6th Jan 1992 |
| 192.75.27.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.28.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.29.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.3.0/24 | 256 | ARIN | CA | 8th Aug 1990 |
| 192.75.30.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.31.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.32.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.33.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.34.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.35.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.36.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.37.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.39.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.40.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.41.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.42.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.44.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.46.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.47.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.49.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.5.0/24 | 256 | ARIN | CA | 8th Aug 1990 |
| 192.75.50.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.51.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.52.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.53.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.54.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.59.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.6.0/24 | 256 | ARIN | CA | 26th Mar 1990 |
| 192.75.60.0/24 | 256 | ARIN | CA | 30th Nov 1990 |
| 192.75.61.0/24 | 256 | ARIN | CA | 30th Nov 1990 |